Key Points

Question  Can a combination of fluorouracil and calcipotriene creams be used safely and effectively as a treatment for refractory extramammary Paget disease (EMPD)?

Findings  In this case series, we report 3 cases of refractory EMPD treated with a topical combination of fluorouracil and calcipotriene. The treatment was well tolerated and was followed by clinical improvement in all cases with demonstrated histopathological response in 2 of the cases.

Meaning  Topical combination of fluorouracil and calcipotriene may be a viable palliative treatment option for patients with refractory EMPD.

Abstract

Importance  Extramammary Paget disease (EMPD), a rare intraepithelial adenocarcinoma, poses a therapeutic challenge with high postoperative recurrence rates and a limited number of effective local treatment options.

Objective  To describe the use and efficacy of a topical combination of fluorouracil and calcipotriene as a palliative therapy for refractory EMPD.

Design, Setting, and Participants  This retrospective case series of 3 women with recurrent, refractory EMPD was conducted at Beth Israel Deaconess Medical Center, Boston, Massachusetts and Washington University School of Medicine, St Louis, Missouri. All patients were treated with a 1:1 mixture of fluorouracil, 5%, cream and calcipotriene, 0.005%, cream or ointment.

Main Outcomes and Measures  Clinical and histopathological findings.

Results  All 3 women (1 in her 50s, 2 in their 70s) presented with recurrent EMPD (vulvar, perianal, and perioral) after surgery and/or irradiation, and their EMPD was refractory to treatment with imiquimod, 5%, cream. Owing to disease progression and/or intolerable adverse effects from imiquimod, the patients began treatment with a 1:1 mixture of fluorouracil, 5%, cream and calcipotriene, 0.005%, cream. This treatment, which was well tolerated, was followed by clinical improvement in symptoms and appearance of the lesions in all 3 cases and histopathological signs of decreased tumor burden in 2 cases. Patients applied the combination topical therapy to affected areas with differing frequencies, ranging from 1 to 2 days per month to 4 consecutive days every 2 weeks.

Conclusions and Relevance  Extramammary Paget disease frequently recurs even after aggressive surgical management and can be refractory to many topical and locoregional therapies. Palliative treatment with a combination of fluorouracil and calcipotriene may be a viable option for patients with recurrent, refractory EMPD.